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Hello, I have encountered a problem. When I am performing a simple mathematical multiplication calculation, if I input 90 in Q0, the data I get in next question (1.4*Q0) is not 126, but 125.99999999999999, as shown in the following figure. I have not encountered this situation at any other time. But I am very concerned that similar situations may occur in the future. Although this has a small actual calculation error. But for the respondents, they will be very confused about this number. How can I avoid this situation? Thank you all

 

See stackoverflow.com/questions/588004/is-fl...ng-point-math-broken for an explanation

You can use round : www.limesurvey.org/manual/ExpressionScri...mplemented_functions